Barrel throat question

[jblackfish]

I have a pre-80 Colt Commander with a barrel throat that is tapered only at the bottom chamber area entrance (dimple cut) and not like most others (traditional) that extend up each side. Would it be reasonable to have a competent smith extend that ramped area farther up the sides? I want to shoot SWC in it - haven't tried them yet - it feeds ball ammo fine but thinking about SWC and hollow point too.

If I should, would Colt be a good place to start for that job? Any other smith suggestions?

 

[RaceM]

Try the ammo first before doing the mod, it may feed just fine as is. "Competent" is the operative word when it comes to smiths. A bad one can turn that into a bill for a new barrel.

 

[jblackfish]

RaceM, I will try some ammo first chance I get. I just though that a more thorough throat job would probably help prevent problems with other-than ball ammo in the future. Here's a pic of that barrel throat - you can see the original machine marks on it. The ramp looks fairly rough too. It's never been touched from the original Colt manufacter:

 

[RaceM]

I'd just go at that with some fine grit sandpaper, 400 then 600, no dremel tool, and polish the machining cut marks out if that is the concern.

When you try feeding the other ammo, do it slowly (ride the slide) at first and see if it hangs up. If it doesn't hang while slow feeding it prolly won't while in full speed operation.

 

[jblackfish]

400-600 grit sandpaper is a little too aggressive for me to start with. I'll try some 1000 grit and take more time. If if I can get a few of the rough marks on the throat and ramp smoothed out I'll polish with some 1500 grit and shoot the SWC's and see how it does. I don't want to change any of the original cut angles at all. If I end up going with the more modern throat config I'll get a pro to do it.

 

[RaceM]

I don't blame ya for going slow (super fine grit). <shrug> I've been doing metalwork for most of my life so I might be a little faster at it . Not using a dremel will preserve the angles. Don't know how many jobs I've seen botched with that speedy little machine .

Good luck with the project. Odds are good that just polishing that ramp will get ya where you want to go.

 

[jblackfish]

I'll never pick up a Dremel in the presence of a firearm (especially 1911) again, not even to polish. I don't have a disaster story to tell - more like a scary "near miss" but enough of a lesson that I can make the previous statement with conviction. I do it by hand (if I can) or I let a pro do it - that's my rule.

 

[1911Tuner]

Have you tried it with hollowpoints and SWCs...or are you just assuming that it'll need work to run with those bullet types? It may do just fine, assuming a proper magazine. I've got original, unaltered USGI pistols and a 1925 Commercial Government Model that can't tell the difference between hardball and hollowpoints and cast H&G #68 semi-wadcutters...and they feed'em from the old "Hardball" magazines.

 

[jblackfish]

I admit I have shot only a few SWC's through it and had no problem. However, one of my inquiries re: a gunsmith came through and I've sent the barrel to him for a throat job. Surely it won't hurt the feeding of any rounds to have the most common throat cut on it instead of the dimple cut.